PIP is installing incompatible version despite error

[Persedes]

Description

If I tell pip to install an incompatible version of a package, it shows an error message, but still installs the incompatible dependency.

ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
virtualenv 20.16.5 requires importlib-metadata>=4.8.3; python_version < "3.8", but you have importlib-metadata 1.7.0 which is incompatible.

Is this expected? See the example below for details.

Expected behavior

The incompatible package version should not be installed.

pip version

22.2.2

Python version

3.7.0.

OS

Debian GNU/Linux 9 (stretch)

How to Reproduce

$ docker run --rm -it python:3.7.0 bash

$ pip install pip --upgrade

# virtualenv depends on importlib_metadata>=4.8.3
$ pip install virtualenv

$ pip install importlib_metadata==1.7.0           

$ pip show importlib_metadata

Output

$ pip install importlib_metadata==1.7.0                                                                  
...
Attempting uninstall: importlib_metadata                                                                                              
Found existing installation: importlib-metadata 4.12.0                                                                               
Uninstalling importlib-metadata-4.12.0:                                                                                                
Successfully uninstalled importlib-metadata-4.12.0                                                                             
ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.                                                                                            
virtualenv 20.16.5 requires importlib-metadata>=4.8.3; python_version < "3.8", but you have importlib-metadata 1.7.0 which is incompatible.                                                                                                                               
Successfully installed importlib_metadata-1.7.0       

$ pip show importlib_metadata                                                                            
Name: importlib-metadata                                                                                                             
Version: 1.7.0                                                                                                                       
Summary: Read metadata from Python packages                                                                                          
Home-page: http://importlib-metadata.readthedocs.io/                                                                                 
Author: Barry Warsaw                                                                                                                 
Author-email: barry@python.org                                                                                                       
License: Apache Software License                                                                                                     
Location: /usr/local/lib/python3.7/site-packages                                                                                     
Requires: zipp                                                                                                                       
Required-by: virtualenv                

Code of Conduct

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[uranusjr]

See #9094